Since the initial report of a hydroboration reaction, the addition of H—B bonds to alkynes has become a widely-used reaction in organic synthesis. The resulting vinyl boranes are versatile intermediates for oxidation, copper-catalyzed conjugate addition, and Suzuki cross-coupling reactions. However, despite the widespread utility of the hydroboration reaction and development of many related X—B bond addition reactions (where X is a non-hydrogen atom), addition by some other types of boron bonds has not been reported.